【阅读理解】As well, there are 2,000 transmitter towers around Australia, many in high density(密度) residential areas. For example, Telstra, Optus and Vodaphone build their towers where it is geographically suitable to them and disregard the need of the community. The radiation emitted from these towers may have already produced some harmful effects on the health of the residents nearby.
Many transmitter towers were built ______.
A.on high mountains. B.in places suitable to the phone users. C.in areas which can take in radiation. D.in densely populated areas.正确答案D
